Ronnie Hillman will likely start at RB for the Broncos in their preseason opener against Seattle on Thursday. (John Leyba, The Denver Post)

Training camp for the Broncos on Monday was consumed by the news of Montee Ball’s absence. The team’s starting running back will undergo an emergency appendectomy this afternoon and will miss at least the first couple of preseason games, including Thursday’s opener against the Seahawks at Sports Authority Field at Mile High.

That means Ronnie Hillman, who had 218 yards on 55 carries in 10 games for the Broncos last season and is No. 2 on the depth chart, will likely start against Seattle.

“I think he’s been a different guy in the meeting rooms with a full offseason this year and attacking it the way he did,” coach John Fox said Monday. “He is starting to see the benefits of that here on the field. I have seen a drastically improved player.”Read more…

Montee Ball fumbles in the third quarter of the Broncos game against the Patriots on November 24. (Jared Wickerham, Getty Images)

Monday night, as I was doing research for my story about the Broncos’ running backs and what on earth is going on on the depth chart behind Knowshon Moreno, I started looking at fumble numbers. The way we talk about Ronnie Hillman, Montee Ball and C.J. Anderson, you’d think they’d committed eight fumbles apiece by this point in the season. But see, they haven’t. Hillman has two, Ball two, and Anderson fumbled and recovered the ball in New England.

My first thought was that it doesn’t sound so terrible.

Then I looked at the numbers.

You see, Ball has just 75 carries, Hillman 40, Anderson seven. That’s good for 41st among all running backs in the NFL, 65th and tied for 106th, respectively. The gist: these guys aren’t getting many carries, but they’re still up there among the worst fumblers in the league.

Yes, it is a big deal that Ronnie Hillman, he of all of the pass blocking issues last season, has seemed to have solved them satisfactorily enough to rise to the top spot among running backs on the Broncos first depth chart released last weekend.

But it is only a big deal to us. Broncos coach John Fox isn’t fazed and won’t be strapped to the depth chart when deciding who trots out on the field first at the position on Sept. 5 against the Ravens.

“Again, it’s going to be based on performance,” Fox said. “We’ve got four preseason games to take a look at them. We have a depth chart. We released a depth chart only because the league makes us, but as it sorts out they’ll define where they fit on the depth chart.”

Although veteran Justin Bannan has been sidelined through most of training camp, he is starting alongside defensive tackle Ty Warren at defensive tackle. As it should be.

Second-round rookie Derek Wolfe, a defensive tackle by trade, is listed as the No. 2 left end behind Jason Hunter. Ideally, Wolfe plays end on running downs and moves inside to tackle in the nickel package. Remember, Von Miller moves from strongside linebacker to end in the nickel.

Kevin Vickerson and Mitch Unrein are the No. 2 defensive tackles with Sealver Siliga, who played with the No. 1 unit throughout the OTAs and minicamp, is third string along with fifth-round rookie Malik Jackson.

Third-round rookie Ronnie Hillman is listed No. 3 but he should have his own category. Call it the X Factor. Hillman has the team made as the speed back.

The No. 2 running back is a competition between Ball and Knowshon Moreno, who is listed at No. 4. Moreno is just returning from knee injury. The decision here is choosing between the dependable, durable and solid-if-not-spectacular Ball and the more talented but less durable and inconsistent Moreno.

It’s possible the Broncos keep four tailbacks but don’t know if it’s probable. Moreno may be on the bubble but his toughness is underrated. He seems to enjoy picking up the blitz and he’s a good receiver. Don’t count him out.

Really no surprise after Manning. The rookie Brock Osweiler can’t be placed ahead of the veteran Caleb Hanie on the first depth chart. Hanie signed a two-year, $2.25 million contract in March but no money is guaranteed until he makes the roster.

The Broncos’ decision makers need to see these quarterbacks perform in the preseason.

“As coach Fox said, the games are our resume,” said Adam Weber, who is listed No. 4 on the depth chart.

Weber could return to the practice squad for a second year. Osweiler, a second-round rookie, will be no worse than the No. 3 quarterback. The question is whether Hanie’s experience fends the kid off at No. 2.

Contrary to depth chart listing, Quinton Carter is not ahead of Mike Adams. Maybe the plan was for Carter to team with Rahim Moore with Adams coming in to run communications with the nickel package.

But Adams has been starting since Carter tried stopping in front of a soccer goalie net July 27 at the sports bubble. And given Carter recently underwent arthroscopic knee surgery and newly signed veteran Jim Leonhard is still rehabbing his knee injury, it’s fairly certain Adams will start Game 1 against Pittsburgh Steelers on Sept. 9.

Nicki Jhabvala is a Broncos beat writer for The Denver Post. She was previously the digital news editor for sports. Before arriving in Denver, she spent five years at Sports Illustrated working primarily as its online NBA editor. She also spent two years as a home page editor at the New York Times.